This study evaluated the water quality characteristics of two widely used indirect water intake methods in Korea—riverbed filtration and riverbank filtration—which have garnered increasing attention in response to recent climate anomalies. Specifically, the study compared water quality data from the Anseongcheon area, where riverbed and riverbank filtration facilities are installed at the same location. Monthly measurements of pH, biochemical oxygen demand (BOD), suspended solids (SS), dissolved oxygen (DO), total coliforms (TC), and fecal coliforms (FC) were conducted from 2016 to 2018. Additionally, five rounds of sampling and analysis of the horizontal wells in the riverbank filtration system were conducted between 2018 and 2019. The results showed that both riverbed and riverbank filtration methods generally produced higher water quality compared to raw river water. While riverbed filtration was particularly effective at removing physical pollutants such as SS and turbidity, riverbank filtration demonstrated superior overall performance by significantly reducing all major water quality indicators. Notably, riverbank filtration exhibited excellent biological treatment efficiency in lowering concentrations of BOD, TC, and FC. This study provides empirical evidence demonstrating the improvement of water quality achieved through indirect water intake methods, offering valuable insights for the selection and management of sustainable water supply strategies in the future.

Keywords: Indirect intake method, Riverbank filtration, Riverbed filtration, Water quality, Water resource